Increased In Vitamin Content and Calcium Content May Result In "Super Lettuce"

Experts with the USDA research service are boosting the nutritional value of iceberg lettuce. The researchers simply pried open the leaves as they grew.

Keeping the lettuce from forming a tightly closed head and with more surface exposed on the open lettuce leaves, more sunlight seeped in. As a result, they found this super lettuce accumulated five times as much vitamin c, and twice as much calcium a iron as the typical lettuce we buy now.